The San Jose Mercury News reports Martinez died of a heart attack Tuesday during a kidney dialysis session. It was his 66th birthday.

At the time of his death, Martinez was awaiting word on a kidney transplant. He also suffered from diabetes.

Brady first met Martinez at a football camp at the college of San Mateo, where Martinez was a successful coach. Brady was just 12 years old at the time.

WBZ-TV’s David Robichaud reports.

Since then, the two became good friends. Every offseason, they would get together and work on Brady’s throwing mechanics and they’d communicate after every Patriots game.

Brady released the following statement on his Facebook page on Martinez’ passing:

‎”I am deeply saddened by the passing of my coach, mentor and friend. Coach Martinez’s invaluable assistance and support will never be forgotten and will always have a lasting impact on my life. The time we spent together remain some of my fondest memories. His legacy of commitment, toughness and determination will live on forever.”

In a story about their relationship that aired on CBS Thanksgiving Day, Brady said he still relied on Martinez to make sure his mechanics were correct.

“I’ve been so fortunate to be kind of his student that would take all this information and hopefully pass it on to the next generation of young quarterbacks that want to learn the proper ways to throw the football,” Brady said.

At the end of the CBS piece, Martinez had this message for all of his students over the years.

“I ask that you take one or two of my life lessons and pass them on to your family and friends. That will keep me alive forever,” said Martinez.

The Patriots released a statement about the passing of Martinez, via Twitter.

“Our sincere condolences go out to the Martinez family & all those he mentored throughout his incredible career,” the statement read.

Julian Edelman, a former college quarterback and Bay Area-native, also Tweeted his condolences:

RIP coach Tom Martinez. He was such a great mentor to many in the bay area. His legacy will always live on.